I've just had this accord 1999 4 door sedan 2.0L automatic 4 speed and just did 80,000kms. I noticed that when my car is in idle and the aircondition is running the idle is okay but in a certain period of time. The idling starts it goes up and down, it only happens when I hear the aircondition does a certain click sound but once its done doing its thing the idling goes proper again.

Also, if I turned off the aircondition when the problem started to happen the car's idling is okay again. The problem doesn't happen while you're driving it but sometimes happen when its on drive but not moving.

I found a thread in this great forum that points to FITV. Do you think this is something to do with FITV? I've also checked the MAP sensor the voltage are correct.

Please help

 

thats your AC condensor kicking on and off. you might notice a little difference in idle RPM's, between 100-250 because your motor is under load when your AC is on. Perfectly normal.

 

unfortunately this one goes really bad jumping from 100-1000rpms like a see saw.

 

EACV (electronic air control valve), Clean it with some carb cleaner.
what about when you turn on your headlights, does it do the same thing

 

THanks I'll try it tomorrow... however, hmm... I dunno where to find or what the EACV looks like for F18B

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by banjuju &raquo;</TD></TR><TR><TD CLASS="quote">THanks I'll try it tomorrow... however, hmm... I dunno where to find or what the EACV looks like for F18B</TD></TR></TABLE>
It's called Idle-Air control valve (IACV). On the F23 here in USA it's located on the back side of the intake manifold (#9). I can only guess that it's about the same down there...

 

i got the same problem, only my fan doesn't turn on.. same solution?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bonh &raquo;</TD></TR><TR><TD CLASS="quote">i got the same problem, only my fan doesn't turn on.. same solution?</TD></TR></TABLE>Cleaning the IACV is one part of it. If your idle is flaky, look for a post about "cleaning IACV & FITV" & read all thru it. There's several things to clean & adjust, & any of them can cause a flaky idle.

The fan not running seems like a separate problem.

 

2nd post bump

 

Yes its kinda doing it when the head lights are on or when I use the central locking. I can here the engine's rev getting abit of grunt and the idle goes lower. Does this mean it kinda points to IACV? If yes... Do you happen to know what would be the right reading for the IACV using a multimeter?

 

The IACV operates in response to loads on the engine. It's not like a sensor where you can check it's signal. The signal comes from the ECU telling the IACV what to do.

Find that thread about 'cleaning IACV...' and check out the part about setting your 'base' idle speed. When you notice this, exactly how far does the rpm drop? ... and what's the normal operating idle?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by accordcd_7 &raquo;</TD></TR><TR><TD CLASS="quote">thats your AC condenser kicking on and off. you might notice a little difference in idle RPM's, between 100-250 because your motor is under load when your AC is on. Perfectly normal.</TD></TR></TABLE>

Actually, its the clutch engaging on the A/C compressor. The condenser is like the engines rad, it sits in the front of the car to cool down the refrigerant, and dissipate excess heat.

The pulley on a AC compressor works sort of like drum brakes. The pulley freewheels when its not on, but when you hit the switch, the clutch locks up on the pulley, much like shoes to a drum and it turns the pump inside, creating load on the engine. The Engine RPM should raise about 500 rpm or so, and stay somewhat steady. When you are driving, the engine is making more power, thats why you dont notice it once your moving, only at idle